Cathode-ray tube assembly



l July 30;'1946. 1R, BEBES s 2,404,899

cATHoDE RAY ATUB@ ASSEMBLY Filed Apk-i1 s, 19.44l

jig. 1.

Patented July 30, 1946l 2,404,899 CATHODE-RAY TUBEI ASSEMBLY John R. Beers, Briarclii Manor, N. Y., assignor to North American Philips Company,

Dobbs Ferry, N. Y.

Inc.,

Application April 3, 1944, Serial No` 529,350

(Cl. Z50-162) Claims.

This invention relates to cathode ray tubes, and more particularly to the assembly of certain elements thereof.

It is an object of the present invention to simplify the assembly of elements of a cathode ray tube. f

It is another object of this invention to provide an assembly of the type aforesaid wherein elements are aligned automatically.

Afurther object of the invention is to improve the accuracy and stability of the alignment of elements of a cathode ray tube.

Another object of the invention is to render the assembly of elements of a cathode ray tube 1 more economical.

which the from the Other objects, and the manner in same are attained, Will be apparent following description.

Cathode ray tubes usually comprise an electron gun, as a source of a well-defined, focussed beam of electrons or cathode rays, and deecting means, most commonly in the form of deflecting plates, for controlling or shifting such beam in dependency upon applied voltages. The electron gun usually includes, apart from a cathode and a grid arranged in front thereof, a number of anodes, for example two, which serve as electronoptical lenses for the system and therefore are instrumental in determining the path of the undeflected electron beam, and the deecting means usually include two pairs of deecting plates one arranged in front of and at right angles to the other, these sets of deeeting plates being instrumental in determining the path of the de:- ected electron beam. Evidently, the accurate and stable alignment of the two or several anodes relative to each other, of the two or several sets of deiiecting plates relative to each other, and finally, of the anodes relative to the deflecting plates is among the most important requirements in cathode ray tube manufacture; yet, prior to the present invention, this alignment invariably constituted a rather serious, time-consuming and uneconomical operation, moreover yielding results that left much to be desired.

The present invention contemplates simplifying and at the same time, improving the assembly of elements of a cathode ray tube and specifically, insuring the accurate and stable alignment thereof, by providing, in place of the complex rod or similar supporting structure of the prior art, a unitary supporting member, preferably a ceramic sleeve, mounted, for example, on the first anode and mounting in turn, in prearranged spatial relationship, the other elements to be aligned individually and collectively, such as a second anode and two sets of deflecting plates. Preferably, this sleeve is cylindrical and slides over the top part of a cylindrical first anode whereaiter the second,

`likewise cylindrical anode having the same outer diameter as the iirst anode, is inserted in the sleeve to rest in spaced relation to the iirst anode, openings such as transverse slots being provided in the sleeve for the purpose of welding supply conductors to the anode.

Two sets of longitudinal slots are arranged at right angles to each other in the top part of the sleeve to accommodate and to x in position both relative to each other and to the anode, two sets of delecting plates which project from the sleeve suiiiciently to have supply conductors welded to their projecting portions. In this manner, the precise and lasting alignment of all elements, individually and collectively, is insured to an extent not heretofore obtained, at a material saving in time and labor.

In' the drawing accompanying the present specication and forming part thereof, one embodiment of my invention is shown diagrammatically by way of example.

In the drawing,

Figure l shows somewhat diagrammatically a longitudinal section of an electron gun-deflecting plate assembly of a cathode ray tube according to the invention.

Fig. 2 is a transverse section taken along line 2--2 of Fig.l l; while Fig. 3 is a perspective view of a supporting sleeve according to the invention.

Referring now to the drawing, l denotes the cathode and 2 the grid of an electron gun assembly forming part of a cathode ray tube. A sleeve 3 mounted on the grid assembly supports insulating, e. g. ceramic members 4 which, in turn, support a sleeve 5 mounting the first anode 6. This anode is cylindrical and includes a number of disc-shaped insets 1 which have apertures 8 for focusing purposes.

A ceramic sleeve 9, likewise cylindrical and having an inner diameter hardly larger than the outer diameter of the iirst anode 6, is slid over this anode to be firmly supported thereon, e. g. by resting on sleeve 5, and to be in perfect alignment with the anode 6. The sleeve 9 may be made of Steatite, Isolantite or other suitable refractory material. Two transverse slots l0 are provided on opposite sides of the bottom part of sleeve 9. A supply conductor Il welded to the anode 6 passes through one of the slots I0 while a lock tab l2 welded to the anode 6, rests in the 2,404,899 il j other slot I0 to assistin preventing displacement n of anode 6 relative to sleeve 9,

. rst anode, and provided with disc-shaped insets I4 having apertures I5, is inserted in sleeve 9 abovethe first anode so as to be positioned in the center portion of sleeve 9, Two transverse slots It are provided on opposite sides of the center portion of thesleeve and a supply conductor i7 is passed through one of the slots I 6 and welded to the second anodeV I3, while a lock tab I8 welded to the anode I3 rests in the other slot I IJ to assist in preventing displacement of anode I 3 relative to sleeve 9.

The bottom and center sections of sleeve 9 are ground to accommodate the cylindrical `anodes 6 and I3 while the top section of sleeve 9 is not ground, a step I9 being thus provided between the ground and unground sections which serves4 as an abutment or stop for the second anode I3.

The top portion of sleeve 9 comprises a set of longitudinal slots 2i! arranged above the second anode I3 and accommodating a pair of deecting plates 2I, and another set `of similar'slots22 arranged above the slots Z and at right angles thereto; and accommodating deilecting plates 23. The slots Ziandjzlsserve to; properlyposition.` the platestwhi'chrnayfbe fastened .in-thel slots in'any g vconventional manner.

vfn; `an preferred embodiment of' the invention, two mica discs 24 Vhavingaccurately punched slots 25 to vrigidly hold the plates are slipped over the top of the sleeve T9 and anchoredin position to assist in' the proper alignrnentv and spacing of theiplates. Matching eyelets 26fin the mica 4discs 2e permit, them'A to -berigi'dly fastened to `each other,` at the desired spacing, with upright nickel rods or `wiresA 21 which', apart lfrom acting as connectors', also serveas conductorsinpthe weld-` ing to the stem leads (not shown in the draws ing).v Metal or mica snubbersv (not shown) based on the mica discs may be provided to supportthe assembly in the bulb neck of the cathode ray tube.

I wish it to be understood that I donot desire to be limited to the exact details of construction and design shown and described, as'various modicatons within the scope ofthe appended claims may suggest themselvesto a person skilled in the art.

Iolaim:

l. In a cathode ray tube, in combination, a Cathode and grid assembly, insulating means mounted on said assembly, a first focussing means mounted on said insulating means, a hollow insulating member mounted on said iirst focussing means, a second focussing means mounted inside said'hollow insulating member, at least one pair 4 ofslots in said hollow-insulatingmemben and delecting.v plates extending through. and mounted in'proper alignment by said slots.

2. In a cathode ray tube, in combination, a cathode and grid assembly, insulating means mounted on said assembly, a rst focussing means mounted on said insulating means, a hollow insulating member mounted on said nrst focussing means, a second vfocussing means mounted inside said hollow insulating member, two

sets of slots in said hollow insulating member.

one set arranged above and at right angles to the other, andtwo pairs of deilecting plates eX- tendingthrough and mounted in proper alignment by said slots' 3. `Ina cathode ray tube, in combination, a cathode and grid assembly, insulating means mounted 0n said assembly, a first focussing means mounted on said insulating means, a hollow insulating member mounted on said rst focussing means, a second'focussing means mounted inside said hollow insulating member, at least one pair of slots in said hollow insulating/member, delecting plates extending through andmounted in proper alignment by said slots, and means surrounding said hollow insulating member andhavl ingslotswhereby tov engage 'saiddelecting plates.

Inaca'thode ray tube, `,in combination,l a

, cathodeand-grid assembly, insulating means mounted on said assemblma rst'focussing means mounted on said insulating means, a hollow in, sulating member mountedfon said first focussing means, asecond focussing means mounted inside said hollow V'insulating member,A atleast one pair of slots in said hollow insulating. membendeilect-L ing ,plates extending' through a-nd'niountedvin proper alignment'byl said slots, and an'annular insulating means having corresponding slots slid over lsaidhollow insulating 'meinberto hold said deiiecting plates in place. 5 i 5; In a cathode ray tube, in* combination, `a cathode and. grid assembly, insulating .means mounted on said assembly, a rst focussing means mounted onsaid insulating means, a hollow insu'- lating member-mounted on said ii'rstfocussing means, a second focussing means mountedinside said hollow insulating member, two sets of slots in said hollow insulating member one set varranged aboveand at right angles to the other, two pairsv of deilecting plates extending through and mounted in proper alignment by saidslots, two annular insulating means having slots where.- by to engage and hold in place said deilecting plates, mounted on said hollow insulating mem-.- ber, and means connecting and spacing said an,- nular insulating means;

Y JOHN R. BEERS. 

